Two temperature refrigerator



March 18, 1952 e. K. IWASHITA TWO- TEMPERATURE REFRIGERATOR Original Filed July 14, 1943 Patented Mar. 18, 1952 TWO .T-EMPERATURE REFRIGERATOR George K. Iwashita,,l\ *utley, N, 1., assiggnor to Admiral Corporation, Chicago Illa. corporation weiaua e,

Original application July ,.1943,,Serial No,

94,629! Divided-a svanr icatiqnnae-. 1,

This. invention relates to refrigerators .and par,- ticularly to refrigerators of the. type having two food storage .compartmentsto. be maintained ,at different temperatures. This application is. a division of the copending application of George K. Iwashita, Serial No. 494,629, filed Ju1y..l4, 1943 and issued on June20, 1950,, into Patent. No. 2,511,851.

A primary object-of this invention is to provide an improved two, temperature, two compartment refrigerator which has advantages-ofconstruc: tion and operation not possessed by prior art refrigerators.

Another objectis to provide an .improved ,two temperature, two compartment. refrigerator of the type having primary and secondary refrigerant circulating circuits.

Another object is to. providean improved two temperaturetwo compartment refrigerator having a, primary circuit provided withv av single evaporator and having -asecondarycircuit arranged so as to be cooled. by the primary evaporawtonand in turn cooling. the second compartment.

Another object is to provide an improved two temperature, two compartment refrigerator having a primary refrigerantcirculating system with a single evaporator which simultaneously refrigerates one, of the compartmentand the 'secondary, condenser.

Another objectis to provide av twoncompartment, two temperature refrigerator wherein the cooler of the two compartments also. effects partial cooling of theothercompartment.

Other objects and-advantages will vbecome-apparent. from the following description taken in conjunction with the accompanying drawing wherein:

Fig. lis a longitudinal medial cross-sectional viewof. a refrigerator embodying the. present in,- vention; and

Fig. 2 is a fragmentary medial cross-sectional view taken onthesame plane as Fig.1 but. show ing the arrangementof the primary evaporator and; secondarycondenser on. the .frost chest in greater detail.

The refrigerator. indicated generally by the ref erence character l 0, includes .a, front frame] 2 to which are secured .a main outer shell and a pair. of compartment. defining liners l 6 and; l 8, the liner [6 defining the frost chest? 20.and. the liner, [8 defining ,themain food storage compar.t-. ment 22. Therefrigerator cabinet also includes a machinery compartment 24 which isclosed at te tunne i eb pa e 26. secured. o.,.the frame l2 and to the outer shell M. The frame of the refrigeratoralso includes a base frame-28'jwhich supports the operating mechanism as willbewdescribed in greater detail hereinafter. The rear of the cabinet is closed by a panel 30 having ,an opening 3| which is closed by a removable panel 32 secured to the panel. 30 by sheet metal screws 3 The space surrounding the liners I6 andi|8 and enclosed by the shell I4,.panels, 26,,30fiand'32 is filled with a suitable thermal insulating ma..- terial 36. This insulating, material may be. of many. different types including, rock wool, ,balsa wool or the like. The access openings to thecompartments Hand 22 are closed by a single door 1580f any suitable construction which is provided with a deformable gasket 40 sealing againstthe frontof the refrigerator. cabinet. The door-.is preferably thermally insulated to prevent the escape of heat therepastu,

The liner [8 is rigidly secured to the frame l2 and is permanently mounted in the cabinet. The

liner l6 forming the frost chest 20 is-removably heldin position against the frame 12 by,means of. a, pair of tensioned straps 42 secured at their forward ends tothe frame l2; their rear ends are secured, together at the back of the frost chest by a connector 44 which may be disconnected soas to provide for removal of the liner l6. Adjacent its rear the frost chest liner I6 is additionally supported by a thermally nonconductive block 46 which is mounted on the outside of the ceiling of the liner [8. The space 4'! forwardly of the block and between the liners I6 and I8 is not filled with thermal insulation and, therefore, there is a heat transfer by convection between the frost, chest 23 and the. compartment 22 through this space.

The compartments 2!) and 22 are cooled bya primary refrigerating system 48 and a secondary refrigerating system 50. The primary systemincludes a. refrigerant liquefier comprising a compressor 52 and a condenser 54 connected thereto. The outlet side of the condenser 54 is connected by a capillary tube 56 to the inlet of primary evaporator coil 58 which is secured to the outside of the liner, !6 in heat exchange relation by metallic Permagum which is a material possessinghigh thermal ponductivity and maybe asoft nonoxodizing material impregnated with aluminum flakes, graphite and the like The evaporator coil 58 is therefore permanently seacured to the outer surface of the liner I 6 and when the. primary system is removed from the refrigerator cabinet the liner It must also be re:- moved. Theoutlet, from the evaporator 58 leads Q.a. -.aQQum1 ,at9 l. ;w i.ch; ,isv con ected ibna suction tube 59' to the compressor 52;

The Secondary system 50 includes a condenser coil 62 connected to an evaporator coil 64 which is secured to the outer surface of the liner l8 in good heat exchange relation. The condenser coil is removably mounted on the side of the liner by means of a bracket 66. The secondary condenser 62 is therefore in heat exchange relation with the walls of the liner l6 and through them with the evaporator 58 of the primary system. The primary evaporator thus directly refrigerates the frost chest and simultaneously extracts heat from the refrigerant in the secondary system in order that the secondary system may Withdraw heat from the larger storage compartment 22.- The secondary condenser 62 is above the secondary evaporator 64 and'the tubing forming this system is so arranged that the flow of refrigerant therethrough will be in one direction.

In order that the cooling of the compartment 22 may be improved, the space between the lower wall of the liner l6 and the upper wall of the liner I8 is left uninsulated, as previously mentioned, allowing heat transfer from the lower liner to the upper liner by convection.

, ,The primary refrigerating system is very readily removed from the cabinet. First the small, panel 32 is removed, and then that part of the, insulation indicated by the reference charac- Iter 68 may be removed without disturbing the restof the insulation 36. This exposes the back of the liner l6, and the fastening 44 is disconlnected. The liner I6 and the attached evaporator coil 58 is slid rearwardly after the secondary condenser coil 62 has been slipped from beneath the clamp 66 and moved to one side. Since the tubing is flexible, this movement of the condenser tubing 62 to one side is very easily carried out. The removal of the primary system from the cabinet is completed by removing the compressor 52 and condenser 54 from the machinery compartment 2d. The primary system can, therefore, be hermetically sealed and, if necessary, returned to the factory for repairs. The primary refrigerant circulating system is replaced in the cabinet by carrying out the foregoing steps in the reverse order.

Itwill be obvious to those skilled in theart that numerous modifications and changes may be made in this refrigerator without departing from the fundamental principles of the invention, which is to be limited only by the scope of the appended claims.

What is claimed as new and desired to be secured by United States Letters Patent is:

1. A refrigerator comprising a liner which forms a low temperature compartment, a second liner spaced from the first which forms a higher temperature compartment, means for insulating both liners on all sides except the space between them, a secondary refrigerating system having a condenser portion in direct heat exchange relation with said low temperature compartment liner and an evaporator portion in direct heat exchange relation with said high temperature compartment liner, and a primary evaporator maintained in heat transfer relation with said low temperature compartment liner whereby it cools both the low temperature compartment and the secondary refrigerant.

2.,A refrigerator comprising a liner which forms a low temperature compartment, a second .liner spaced from the first which forms a higher temperature compartment, means for insulating both liners on all sides except the space between 'relation with said low temperature compartment liner whereby it cools both the low temperature compartment and the secondary refrigerant, the cooling of the higher temperature compartment being accomplished both by the secondary refrigerant and by convection in the uninsulated space between the liners.

3. A refrigerator comprising a liner which forms an upper low temperature compartment, a second liner spaced downwardly from the first which forms a lower high temperature compartment, means for insulating both liners on all sides except the space between them, a secondary refrigerating system having a condenser portion in heat exchange relation with said low temperature compartment liner and an evaporator portion in heat exchange relation with said high temperature compartment liner, and a primary evaporator maintained in heat transfer relation with said low temperature compartment liner whereby it cools both the low temperature compartment and the secondary refrigerant, the cooling of the higher temperature compartment being accomplished both by the secondary refrigerant and by convection in the uninsulated space between the liners.

4. A refrigerator comprising a liner which forms a low temperature compartment, a second liner spaced from the first and which forms a high temperature compartment, a secondary refrigerating system having a secondary condenser portion and having a heat absorbing portion in heat exchange relation with said high temperature compartment liner, and a primary refrigerating system having an evaporator coil in heat absorbing relation with both said low temperature compartment liner and said condenser portion of said secondary refrigerating system, said condenser portion of said secondary refrigerating system being in direct heat exchange contact with said low temperature compartment liner.

5. A refrigerator comprising a liner which forms a low temperature compartment, a second liner spaced from the first which forms a high temperature compartment, a secondary refrigerating system having a secondary condenser portion and having a heat absorbing portion in heat exchange relation with said high temperature compartment liner, and a primary refrigerating system removable from the refrigerator having an evaporator coil in heat absorbing relation with both said low temperature compartment liner and said condenser portion of said secondary refrigerating system, said condenser portion of said secondary refrigerating system being removably held in heat exchange contact with said low temperature compartment liner.

6. A refrigerator comprising a removable liner which forms a low temperature compartment, a second liner spaced from the first which forms a high temperature compartment, a secondary refrigerating system having a condenser portion and having a heat absorbing portion in heat exchange relation with the high temperature compartment liner, and a primary refrigerating system having an evaporator coil secured to and in heat absorbing relation with said low temperature compartment liner, and. means removably securing said condenser portion of said secondary refrigerating system in heat exchange contact with said low temperature compartment liner whereby said primary evaporator coil refrigerates both said low temperature compartment and said secondary condenser.

7. A refrigerator comprising a removable liner which forms a low temperature compartment, a second liner spaced from the first which forms a high temperature compartment, thermal insulation surrounding said liners on all sides except the space between them, a secondary refrigerating system having a condenser portion and having a heat absorbing portion in heat exchange relation with the high temperature compartment liner, and a primary refrigerating system having an evaporator coil secured to and in heat absorbing relation with said low temperature compartment liner; and means removably securing said condenser portion of said secondary refrigerating system in heat exchange contact with said low temperature compartment liner whereby said primary evaporator coil refrigerates both said low temperature compartment and said secondary condenser and the cooling of said high temperature compartment is accomplished both by said secondary heat absorbing portion and by convection in the uninsulated space between said liners.

GEORGE K. IWASHITA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,798,951 Munters Mar. 31, 1931 1,865,513 Gaugler July 5, 1932 1,926,384 Hull Sept. 12, 1933 2,035,573 Smith Mar. 31, 1936 2,101,656 Steenstrup Dec. 7, 1937 2,309,797 Stickel Feb. 2, 1943 2,405,392 Atchison Aug. 6, 1946 2,416,354 Shoemaker Feb. 25, 1947 2,416,777 Schweller Mar. 4, 1947 FOREIGN PATENTS Number Country Date 575,5 5 Germany Apr. 28, 1933 

